Field of the Invention
The present invention relates to an image pickup apparatus.
Description of the Related Art
Hitherto, in a single-lens reflex camera system in which lenses can be interchanged, in general, a through the lens (TTL) phase difference focus detection method is used. In the case of a single-lens reflex camera system, normally, a photographing lens is detachably mounted to a camera body. Because each photographing lens has a different level of manufacturing error, a focus position is different for each photographing lens.
In Japanese Patent No. 4378141, there is described a method of correcting the focus position by taking images while shifting the focus position by a small amount forward or backward from an auto focus (AF) focus position adjusted during manufacturing, selecting the photographed image that best matches the focus position desired by the user, and using that relative shifted amount as an AF correction value.
In Japanese Patent Application Laid-Open No. 2011-2848, there is described a method of correcting the focus position by taking images while shifting the focus position by a small amount forward or backward from an AF focus position adjusted during manufacturing for each lens, selecting the photographed image that best matches the focus position desired by the user, and using that relative shifted amount as an AF correction value. Further, in Japanese Patent Application Laid-Open No. 2011-2848, there is described a method of switching operation based on a selection state of a photography mode and a normal photography mode.